convert class 'char' to class 'logical' , How?

I have some binary bits in a string of class 'char':

b= 10001010101010101000000111110000111

I wish to covert class of 'b' from 'char' to 'logical'.

When i use str2num function, it considers all the bits as a single number and returns me

str2num(b)

ans =

1.0001e+034

Which i don't want. i want b as a logical array.

Kindly Help.

Answer 1

[Mischa Kim]

Try

b_bin = logical(b(:)'-'0')

[Furqan Haider]

Thank you, that is exactly what i wanted.

[Michael Pugh]

This works but I can't really understand it. Clever though.

[Linden Yuan]

@Michael Pugh Another solution that works is

b_bin = logical(b'-'0')

The -'0' part tells Matlab to subtract the ASCII value of 0, namely 48, from the ASCII values of b', which will be 48 or 49 depending on whether the entry is 0 or 1. In the end, b'-'0' will be a vector of doubles, and we convert that to a logical vector. (See also https://stackoverflow.com/questions/20032413/matlab-string-vector-character-subtraction .)

[Saravanakumar Chandrasekaran]

b= '10001010101010101000000111110000111'

b_bin = logical(b(:)'-'0')

How to convert back the b_bin to b

[James Tursa]

b = char(b_bin+'0')

[Thushara]

"b_bin = logical(b(:)'-'0')"

Why this is not indicated in the Documentation for 'logical' function?

[Stephen23]

"Why this is not indicated in the Documentation for 'logical' function?"

It already is: it states at the very top "logical(A) converts A into an array of logical values. Any nonzero element of A is converted to logical 1 (true) and zeros are converted to logical 0 (false)", which is exactly what happens here.

Of course the LOGICAL documentation cannot cover every possible way that you might create the input array (you did not consider that there are many many many many other ways of creating the input array and there is nothing special about this particular way so your proposal would mean including basically a very large subset of the entire MATLAB documentation on every single MATLAB documentation page... such documentation would be truly very large and very difficult to find anything in).

Answer 2

[William Prophet]

If you want to convert the character array to a logical one, just compare the entire array character by character. So if you have '001011' and you want to return [0 0 1 0 1 1], just do

'001011' == '1'

And then every character in the array is compared to '1'.

[Stephen23]

+1 brilliant

Answer 3

[Andreas Goser]

Logical can only hold 0 or 1, so 10001010101010101000000111110000111 is not possible. Maybe you want binary numbers?

[Furqan Haider]

yes, you are right, binary holds 0 and 1, but i have a variable 'b' of class 'char' , i want to separate its elements and put them in a logical or 'double' class array.

How can I get it,

Kindly help

[Furqan Haider]

as i have already stated that class of variable 'b' is 'char',

b= ['10001010101010101000000111110000111']